Apparatus and process for forming tubular bodies

ABSTRACT

An apparatus and process for the automatic fabrication of tubular bodies from an inner core and a blank of outer wrap material to envelop the core which is stationarily secured within the wrap and bounded by a pair of end caps. The process and the apparatus for carrying out the process includes cutting means for dimensioning the blank, flanging means for forming opposed side flanges on the blank, wrapper-seamer means for wrapping with the blank a properly oriented inner core and seaming the flanged sides, second flanging means for flanging the ends of the tubular body and end cap mounting means and seamer means all of which operate in an automatic production line.

United States Patent Small 1 51 Nov. 20, 1973 [54] APPARATUS AND PROCESS FOR FORMING 1,668,508 5/1928 Kettering 29/4739 TUBULAR BODIES 2,305,635 9/ 1957 2,264,524 12/1941 Inventor: n rd J. Small, 8343 S. 3,248,791 5/1966 Powers 29/460 Winchester Ave., Chicago, Ill. 60620 Primary ExaminerCharles W. Lanham [22] Filed: Nov. 3, 1971 Assistant ExaminerM. J. Keenan pp No: 195,162 Att0rneyCharles B. Cannon Related US. Application Data 1 [57] ABSTRACT [62] Ser No. 848,512 Aug 1969 An apparatus and process for the automatic fabrication of tubular bodies from an inner core and a blank 52 U.S. c1.....- 29/157 R, 29/200 A, 29/200 B, Wrap material P me which is 113/1 R stationarily secured within the wrap and bounded by a 51 Int. Cl. 1123 19/00 P end P The Process and the apparatus 5s Field at Search 29/157 R, 200 R, carrying Pmcess includes Ming means A, B 20 D 200 J, 200 P, 208 mensioning the blank, flanging means for fOl'Ulil'lg 0p- R, 20 D, F, 0 432.1, 7 posed side flanges on the blank, wrapper-seamer 474 1; 113/1 R l E, l G means for wrapping with the blank a properly oriented inner core and seaming the flanged sides, second [56] References Cited flaggingdmeans for Hanging the ends of the tubular be an end ca mountin means and seamer means UNITED STATES PATENTS all (if which Opel te in an futomatic production line. 3,479,725 11/1969 Shaff et a1 29/157 R 2,187,43l 1/1940 Powell 9 Claims, 32 Drawing 2,234,450 3/1941 Quamstrom..... 3,646,657 3/1972 Small 29/157 R PAIENIEDmvzo 191s SHEEI USUF 17 SHKEI 1101 17 PAIENTEUnuv 20 ms 7 PAIENIEDnuveo ms SHEET 12UF 17 APPARATUS AND PROCESS FOR FORMING TUBULAR BODIES This application is a division of applicants copending application, Ser. No. 848,512 now US. Pat. No. 3,646,657, filed Aug. 8, 1969 on Apparatus and Process for Forming Tubular Bodies.

The present invention relates to both an apparatus and process for the formation of enclosed bodies. More particularly the present invention relates to an apparatus and process for the continuous automatic fabrication of automotive mufflers from an inner core and a blank of wrap material which envelops the inner core which is stationarily secured within the wrap and bounded by a pair of end caps.

Heretofore the formation of automotive mufflers has been carried out on basically what might be considered a manual operation or a series of sequential manual operations during which the mufflers were assembled, seamed, and capped at a number of different operating stations by a number of machine operators.

While the muffler manufactured in this manner suffers in no way from an operational standpoint the thrust throughout not only the mufi'ler industry but throughout most present day industries is toward greater or total mechanization. In this manner quality may be enhanced output may be increased to meet market demands.

However, although the thrust has been toward mechanization no system of muffler fabrication has, as yet, received acceptance throughout the industry.

The present invention, therefore, comtemplates the provision of an assembly line system for the complete assembly of an automotive muffler during which and wherein the individual component parts are automatically assembled and formed together into a completed muffler.

One aspect of the invention contemplates an assembly system that broadly includes means to feed from coiled sheet stock a length of material for use as an outer wrap in the fabrication process. From the stock a predetermined length of material defining a section of material is cut upon demand of the system. Prior to cutting the sheet is caused to pass along a conveyor which functions to straighten or at least substantially relieves the tendence in the stock to bow and return to its previous coiled condition.

The section once cut and embossed as desired, is transported into a flanger unit within which a flange is applied along the full length of the uncut sides. The sec tion to be flanged may, immediately prior thereto, have been cut from the stock or the section may be from stock and introduced to the system immediately prior to the stage. Irrespective of the source the feed of the section is automatically responsive to system demand.

The doubled flanged section is transported to the first assembly station. At a feed table for the assembly station, or the wrapper-seamer, a layer of asbestos, cut to proper size from a supply, is automatically or otherwise located on the section between the flanges. The asbestos provides a lining between the outer wrap and the oval inner muffler core later to be received at the feed table for movement with the lined section for assembly.

A second conveyor system driven in sychronism with the conveyed flanged sections is responsive to the presence of a lined sheet at the table entrance to a seamer and wrapper apparatus thereby to provide and orient a generally oval inner core in relation to the lined flanged section. The inner core is suitably separately supported above the lined flanged section after movement into the wrapper-seamer assembly so that upon movement of a ram the inner core may be wrapped. After wrapping, a seam is formed along the length of the muffler by the sequential movement of a plurality of knives which act on the side flanges thereby to form a lock seam.

The present invention contemplates that the seam may be formed to be parallel either axis of the core.

Therefore, the inner core is suitably oriented for movement into the seamer with this thought in mind. In the present embodiment to be discussed in detail, however, the seam is to be formed adjacent the end of the major axis. However, if the inner core is circular or in some other accepted configuration other considerations are required.

The seam is formed by sequential movement of a plurality of knives located adjacent the flanges. These knives function to create, with proper flange movement, a lock seam secures secured the inner core and forms with the outer wrap a tubular body.

The seamed unit is conveyed by an accumulator to a further stage of the system wherein a short lateral flange or head is formed at both ends of the tubular body. These flanges adapt the body for receipt of a pair of end caps thereby to form a completed unit.

A second accumulator, which functions in a fashion similar to the first accumulator, receives the endflanged unit for transport to the cap assembly station. The end caps may be automatically fed from a pair of spaced magazines and frictionally received over the flange or bead to seal the interior core. As the inner core is provided with passages for communication with both the exhaust and tailpipes care is exercised to properly align the end caps on the tubular body. In this manner the exhaust and tailpipe may be properly mounted.

Final seaming of the end caps to the outer wrap completes the process to be discussed in greater detail hereinafter.

The invention also contemplates the provision of a novel accumulator conveyor which transports, upon controlled need of the system, mufflers in stages of completion between various assembly and operative stations of the overall system. The conveyor allows for the accumulation between stations of the partially completed mufflers to allow for an increase in the rate of production of the overall system. The conveyor allows for the accumulation between stations of the partially completed mufilers to allow for an increase in the rate of production of the overall system to approximately 360 mufflers per hour. In this connection the conveyor path is significantly lengthened from the otherwise straight path between stations. Additionally, stock inventory may be introduced to the conveyor for delivery to following stations during periods of partial shutdown. Further still, the conveyor includes means whereby the seamed muffler, introduced to the conveyor in one position, may be reoriented during transit to a second position thereby to be properly aligned for further processing.

The invention also contemplates as a further aspect a novel end flanger for flanging simultaneously the op posite ends of the tubular body. In this connection the end flanger forms around the entire periphery of the tubular body a flange so that the body may frictionally receive a pair of end caps to enclose the inner core.

In view of the foregoing brief consideration and the following more detailed discussion it will be apparent that the system is adaptable to varied needs and considerations and functions in a manner so as to carry out the objects and provide the benefits and advantages attributable thereto.

In carrying out the several objects the invention contemplates a method for automatically fabricating an automotive muffler comprising providing a blank of sheet material having predetermined dimensional characteristics, transporting said blank through the system in which opposed longitudinal sides of the blank are seamed after enwrapping an hereinafter defined inner core to form an open ended tubular member, transporting an inner core in synchronism with said transported blank and orienting said inner core with respect to said blank at said station to enable it to be wrapped, applying end capping elements to said tubular member for enclosing said inner core, and sealing said elements to said member.

The objects are further carried out by a system for the automatic fabrication of automotive mufflers, the combination comprising a blank of sheet material having predetermined dimensional characteristics; motive means for transporting said blank through said system including a wrapper and seamer unit for wrapping said blank around an hereinafter defined inner core and seaming the joined longitudinal edges of said blank to enclose said inner core and form a tubular member, a flanger unit for forming a flange around the periphery at the open ends of the member for receipt of a pair of end caps, and a seamer unit for securing said end caps at said open ends to enclosed said inner core; and second motive means responsive to movement of said first motive means for transporting said inner core in synchronism with the movement of said blank thereby to orient the inner core in relation to said blank to travel in consort therewith whereby said inner core is enwrapped in said blank and secured by said end caps within the aforementioned units.

Additional objects are carried out by the provision of an apparatus for use in a fabricating system comprising an endless conveyor connecting states of the system and for conveying partially fabricated articles between said stages through an elongated passage which is greater than the distance between said stages, means for driving said conveyor in response to system demands and in synchronism to movement of said partially completed article through said system, means carried by said conveyor for supporting an article throughout movement in the elongated passage between an article inlet and an article outlet, said support means being mounted by the coneyor in a manner such that upon movement of the conveyor said support means is positioned to receive said article from an immediately preceding stage, means in said conveyor path for reorienting the received article from an inlet position to a second position, and outlet means for passing said reoriented article to a following stage of said system.

There have thus been outlined rather broadly the more impostant features of the invention in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures for carrying out the several aspects of the invention. It is important, therefore, that the claims be regarded as including such equivalent constructions as do not depart from the spirit and scope of the invention.

A specific application of the invention has been chosen for purpose of illustration and description, and is shown in the accompanying drawings forming a part of the specification, wherein:

FIG. 1 is a schematic block diagram of the operational stages included in the fabrication process;

FIG. 1A is a schematic block diagram of the operational stages of a modified fabrication process;

FIG. 2 is a side elevation of a portion of the system of FIG. 1;

FIG. 3 is a side elevation of an additional portion of the system of FIG. 1;

FIG. 4 is a top plan view of the structure as shown in FIGS. 2 and 3;

FIG. 5 is a side elevation of an additional portion of the system of FIG. 1;

FIG. 5A is a view similar to FIG. 5 yet viewing the system from the opposite side;

FIG. 6 is a side elevation of a further portion of the system of FIG. 1;

FIG. 6A is a view similar to FIG. 6 showing a portion of the structure from the opposite side;

FIG. 7 is a top plan view of the apparatus of FIG. 5;

FIG. 7A is a view similar to FIG. 7;

FIG. 8 is a top plan view of the apparatus of FIG. 6;

FIG. 8A is a view similar to FIG. 8;

FIG. 9 is a side elevation of the terminal apparatus of FIG. 6 from the opposite direction;

FIG. 10 is a partial side view of a portion of the structure of FIG. 9;

FIG. 11 is a top plan view of the structure of FIG. 10;

FIG. 12 is a vertical section as seen along the line 12 12 in FIG. 10;

FIG. 13 is a side elevation of the accumulator conveyor;

FIG. 14 is a vertical section as seen along the line 14 14 in FIG. 13;

FIG. 15 is a vertical section as seen along the line 15 15 in FIG. 14;

FIG. 16 is an enlarged view of the drive means for the accumulator conveyor;

FIG. 17 is a front elevation of the drive means as seen along the line 17 17 in FIG. 16;

FIG. 18 is a side elevation of the inner core member conveyor;

FIG. 19 is a top plan view of the conveyor of FIG. 18;

FIG. 20 is a front elevation of the conveyor of FIG. 18;

FIG. 21 and 22 are views in cross-section showing sequentially the rollers for folding the seam in the outer wrapping;

FIG. 23 is a side elevation of a sheet transport table;

FIG. 24 is a top plan view of the transport table of FIG. 23;

FIG. 25 is a vertical section as seen along the line 25 25 in FIG. 23;

FIG. 26 is a side elevation of the hump table; and

FIG. 27 is a front elevation of the table as seen in the direction of the line 27 27 in FIG. 26. 

1. A method for automatically fabricating automotive mufflers from a blank of sheet material having predetermined dimensional characteristics, said method comprising in combination the steps of transporting said blank sequentially through an automatic fabrication system including transporting by conveyor means said blank to a wrapper and seamer unit, wrapping said blank around a hereinafter defined inner core and thence seaming the joined longitudinal edges of said blank to enclose said inner core forming a tubular member in said wrapper and seamer unit, transporting by conveyor means said so formed tubular member to a flanger unit, forming a flange around the periphery at each open end of the member for receiving a pair of end caps and thence transporting by conveyor means said tubular member to a seamer unit, securing said end caps at said open ends to enclose said inner core in said seamer unit, while simultaneously transporting sAid inner core by conveyor means in synchronism with the movement of said blank thereby orienting said inner core in relation to said blank to travel in consort therewith, whereby said inner core is enwrapped in said blank and secured by said end caps within the aforementioned units.
 2. A method according to claim 1 further including the step of feeding sheet material from a reeling apparatus carrying a coiled reel of said sheet material, and cutting said blank of predetermined dimensional characteristics from said sheet material.
 3. A method according to claim 1 further including the step of forming longitudinal flanges along opposite sides of said blank prior to transporting said blank to said wrapper and seamer unit.
 4. A method according to claim 1 wherein said wrapper and seamer unit includes a ram movable generally along the axis of said unit, said method further comprising the step of moving and stationarily disposing said inner core in the path of movement of said ram, whereby movement of said ram wraps said blank partially around said inner core.
 5. A method according to claim 4 further comprising the step of subjecting said blank to a plurality of sequentially operable members disposed adjacent the unwrapped portion of said inner core to fully enwrap said core and form a longitudinal seam.
 6. A method according to claim 5 further including the step of bending said seam onto said enclosing wrap.
 7. A method according to claim 1 further comprising the steps of moving said tubular member along elongated paths of travel between said units.
 8. A method according to claim 7 further comprising the step of reorienting the disposition of said tubular member during transit along said elongated paths of travel.
 9. A method according to claim 1 wherein said flanger unit comprises a housing, a pair of elements supported for reciprocable movement within the housing along a common axis, said method further comprising the steps of positioning and supporting said tubular member within said housing so that its longitudinal axis is substantially coincident with said common axis, thereby to be in position for forming said peripheral flange. 